Abstract: The horizontally opposed center fired engine improves on the traditional design of the horizontally opposed engines and center fired engines with a better engine geometry. The present invention utilizes four pairs of opposing pistons to compress a larger volume of air-fuel mixture within four different cylinders. The four different cylinders are radially positioned around a center axle in order to achieve a perfectly symmetric engine geometry. The center axle consists of two different shafts spinning in two different directions, which could drastically reduce engine vibrations in the present invention. Engine vibrations are caused by a change in engine speed and result in a loss of energy. Due to the design, the present invention will only experience energy loss in the form of entropy and friction. Thus, the present invention can convert a higher percentage of chemical energy into mechanical energy than any other internal combustion engine.

Abstract: A rotary valve engine using a single rotary valve serving multiple cylinders significantly increases both volumetric and thermodynamic efficiencies. A novel stratified three stage low temperature combustion system reduces both heat transfer loss and combustion process irreversibility. Using large intake and exhaust valves and passages to reduce throttling losses, the rotary valve also contains a combustion valve and passage connected to a central combustion chamber. Combustion is initiated for all cylinders by a fuel injector in this central chamber which then sequentially ignites a second combustion chamber charge located in each cylinder head. A passage in the rotary valve shaft transfers gas from the combustion cycle to the compression cycle varying the compression ratio of the engine, producing EGR, and transferring radical species for combustion to the next cycle. A compounding element on the rotary valve extracts additional thermal energy derived from reduced heat transfer loss and increased energy.